Segment reporting - Selected Balance Sheet information (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Assets	$ 73,045,383	$ 70,758,155	$ 67,637,917
Deposits	64,884,345	63,618,243
Puerto Rico
Segment Reporting Information [Line Items]
Assets	55,888,211	54,181,300	53,541,427
Loans	24,154,610	22,519,961	20,884,442
Deposits	52,099,309	51,282,007	51,138,790
Popular U.S.
Segment Reporting Information [Line Items]
Assets	15,890,339	15,343,156	12,718,775
Loans	12,431,859	12,006,012	10,643,964
Deposits	11,030,879	10,643,602	8,182,702
Other
Segment Reporting Information [Line Items]
Assets	1,266,833	1,233,699	1,377,715
Loans	526,606	543,299	554,744
Deposits	$ 1,754,157	$ 1,692,634	$ 1,905,735